class TennisScorer
  def initialize
    @server = 0
    @receiver = 0
    @deuce = false
    @advantageServer = false
    @advantageReceiver = false
  end
  
  def scoreServer
    if @server == 0 || @server == 15
      @server = @server + 15;
    end
    if @server == 30
      @server = @server + 10
      if @server == @receiver
        @deuce = true
      end
    end
  end
end